Link httpfs in WASM build

[adsharma]

Summary

• build the httpfs extension as part of the WASM package build
• statically link httpfs into the WASM artifact so s3:// and xet:// URLs are available

Validation

• ruby -e 'require "yaml"; YAML.load_file(".github/workflows/wasm-workflow.yml"); puts "ok"'
• git diff --check -- .github/workflows/wasm-workflow.yml